With the continual increase in the density and load-carrying capability of electronic components on circuit boards, and the consequent increase in heating problems resulting therefrom, axial-flow fans are increasingly being used in an effort to combat such heating problems. During the design of such axial-flow fans, it is important to make them as small and as cost-effective as possible. In particular, it is important to reduce the width of such a fan as much as possible.
Various structures have been used to mount and insulate the stator assembly within a motor, and more particularly, within an axial-flow fan motor. For example, in U.S. Pat. No. 5,264,748, a two-part insulator section is placed over the stator core, and the windings are wound over the insulator section. Pins secured to the insulator section are used to mount the stator on a printed circuit board assembly. The pins are also used to electrically connect the windings to the circuit board. However, the insulator section and the windings add bulk to the stator assembly, causing the motor to be wider than optimal for use in axial-flow fans for cooling electronic components. The use of the insulator section also adds cost to the assembly.
In another structure, a two-part insulator section is attached to the stator core, with the windings wound over the insulator section, in a manner similar to that shown in U.S. Pat. No. 5,264,748. However, instead of using pins to secure the stator assembly to the printed circuit board, the lower part of the insulator section includes legs which protrude below the stator assembly and the legs include means for attachment to the printed circuit board. In this structure, the lead wires for the stator windings are fed through a channel in the legs to the circuit board for connection thereto. Here again, the use of an insulator section between the windings and the core where the insulator section also attaches the stator assembly to the printed circuit boards causes the motor to be wider than optimal and adds cost to the stator assembly.